Jennifer Lopez just can’t seem to stay away from her ex-husband, Marc Anthony. While her boy toy boyfriend was out in Los Angeles choreographing her American Idolperformance, JLo stayed behind in NYC with her ex, RadarOnline.com has learned, even staying at the same hotel!

In town for the NuvoTV up fronts, JLo shacked up at Marc’s fave spot, ironically named The Mark. Her boyfriend was back in Los Angeles, but her ex was in town for the Telemundo up fronts, and stayed at the Upper East Side spot as well, according to a source.

“She previously stayed at The London, so it definitely seemed suspicious,” an insider tells RadarOnline.com exclusively. “The London is almost two miles closer to where the up fronts are, so it seemed like she was just staying at The Mark to be closer to Mark.”

And while the former spouses were too busy to organize any public time together this week, they have a history of secret rendezvous at that hotel.

Back in January, JLo sent Casper out of town just in time for her to meet up with her ex for two hours at The Mark, as RadarOnline.com previously reported.